Methamphetamines release 1250 units of dopamine while sex releases 200
The brain can no longer register a natural level of happiness after its use
'Tweaking' is the most dangerous stage of the addiction cycle, where users become violent and exhibit 'superhuman strength'

Taking methamphetamines feels six times better than having sex, according to a New Zealand ice expert.

Former drug detective, Mike Sabin, explained at a summit on methamphetamine in Melbourne's south-east on Thursday, why the drug is so addictive from the first use.

It trumps the 200 units released during sex and the 100 units of dopamine which are released by everyday normal life pleasures like eating.

However it also completely exceeds the pleasure felt by other drugs, releasing three times more dopamine than the 400 units released by cocaine.

Mr Sabin explained ice causes such extensive damage to the brain, that the neurons which receive pleasurable feelings shut down, unable to register the tiny amounts of dopamine which are natural.

Former drug detective and New Zealand MP, Mike Sabin, attended the Victorian methamphetamine summit on Thursday and Friday to advise the government on how to combat the drug's growth

Addictions thus begin because users end up taking the drug simply 'to try to feel normal'.

'It hijacks the reward pathways of the brain very rapidly,' Mr Sabin told the MailOnline.

'Because the reward pathways are fundamental mechanisms for survival behavior, the use of it becomes stronger than the will to live itself. The addiction occurs because the only thing that brings the return of pleasure and removes dysphoria is continued use.'

From the first use, meth users are at risk of becoming stuck in the cycle of addiction.

This cycle begins with a rush that lasts five to 30 minutes before the user hits a high.

It is during the high that the physical symptoms become apparent, according to Mr Sabin.

'They become highly stimulated. They move quicker, their heart is pumping faster and they see and perceive things around them in a complete different way,' he said.

It is not uncommon at this stage, for ice users to suffer heart attacks. With a normal heart rate considered to be between 60-80 beats a minute, a person who is high on ice can have a heart rate of up to 210 beats a minute.

Presented with an inability to feel regularly happy, the next phase for users is to binge. This involves taking ice non-stop without sleeping for three to five days, with some cases even lasting ten days.

After this point, the stage named 'tweaking' is when the most dangerous and psychotic behaviour occurs, according to Mr Sabin, who recalled a case where a father decapitated two of his children and stabbed a neighbour.